1. Technical Field:
This invention relates to tamper-indicating caps and registering conforming container neck finishes on blow molded plastic jugs which are widely used in the dairy industry and others for expendible packaging of dairy products and the like.
2. Description of the Prior Art:
Prior art devices of this type have relied on a variety of different cap and neck finish configurations. See for example a first group of U.S. Pat. Nos. 3,980,195, 4,354,609, 4,402,415, 4,561,553, and a second group of U.S. Pat. Nos. 2,162,711, 2,162,712, 3,650,428, 4,418,828, 4,497,765, 4,534,480, 3,504,818 and a third group of configurations, U.S. Pat. Nos. 1,443,682, 4,852,774 and 5,004,114.
In the first and second group of the above-referred to U.S. Patents, they are directed towards individual neck and cap spiral thread configuration and have the common fault of requiring selective testing rotation of the cap on the threaded neck of the container before the single thread portions engage.
The patents included in the third group are directed to selective multiple thread configurations with specific reference now to U.S. Pat. No. 1,443,682, a thread pattern is disclosed having non-overlapping thread elements.
U.S. Pat No. 4,852,774 is directed towards a container cap having a plurality of short arcuate inner threads adjacent the outer end of the cap.
U.S. Pat. No. 5,004,114 shows only the container with a neck finish having a plurality of inter-engaging twist threads.